Magnetic Attapulgite Nanoclay Decorated with Surface Imprinted Polymer Thin Film for Enhanced Selective Recognition and Adsorption of Sulfamethazine

Herein, we presented a simple synthetic strategy for fabricating magnetic nanoparticles uniformly dispersed on the surface of attapulgite (ATP), namely the impregnation and pyrolysis method. Subsequently, using magnetic attapulgite as supported core through chemical modification, a novel surface molecularly imprinted nanomaterial (named as MATP/MIPs) was prepared via precipitation polymerization. The obtained MATP/MIPs showed excellent properties by a variety of characterizations including FT-IR, SEM, TEM, VSM, XRD and TGA. Moreover, the adsorption experiments were carried out in aqueous medium at different temperatures, to study the adsorption isotherm, adsorption kinetics and selective recognition ability of MATP/MIPs toward sulfamethazine (SMZ). The experimental data were fitted to the Freundlich isotherm model better than to the Langmuir model. The equilibrium adsorption capacity for SMZ onto MATP/MIPs is higher than onto MATP/NIPs, demonstrating the existence of imprinted cavities. Due to the advantage of coated nanoshell, the adsorption equilibrium was achieved quickly within 45 min, and the data were well-described by the pseudo-second-order kinetic mode. Compared with other antibiotics, the MATP/MIPs exhibited excellent selectivity for SMZ. In addition, the imprinted material still showed good regeneration ability after 10 cycles which make it possible for practical application in the recognition and separation of antibiotics.